I have a 2001 formula with a 3.23 and a 3600 stall Vigilante. The car runs great at speed and wide open throttle (12.20 at track). When I slow up in drive and the rpms drop to 1000-1200 there is a growling sound from the trans..until I shift down manually and raise the rpms to 1500ish.. Do I need a 4.10 gear? Car is used primarily for bracket racing..I drive to and from the track..Thanks
